HTTP implementation based on elasticsearch-nio

[Tim-Brooks]

This is related to #27260. We will need a working http plugin based on the elasticsearch-nio work. This should have feature parity with our other http implementations. This means supporting:

• cors
• pipeling
• normal http plugin settings (https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-http.html)
• HTTP/1.1

[jasontedor]

FYI @elastic/es-core-infra.

[spinscale]

super minor, but just to add it here for the sake of completeness: usage of the X-Opaque-Id in Netty4HttpChannel, a header that is passed from the request to the response for identification purposes